Label the five major parts of a nuclear reactor and describe each part

Most nuclear electricity is generated using just two kinds of reactors which were developed in the 1950s and improved since.
New designs are coming forward and some are in operation as the first generation reactors come to the end of their operating lives.
Over 11% of the world's electricity is produced from nuclear energy, more than from all sources worldwide in 1960.
This paper is about the main conventional types of nuclear reactor. For more advanced types, see Advanced Reactors and Small Reactors papers, and also Generation IV reactors.A nuclear reactor produces and controls the release of energy from splitting the atoms of certain elements. In a nuclear power reactor, the energy released is used as heat to make steam to generate electricity. (In a research reactor the main purpose is to utilise the actual neutrons produced in the core. In most naval reactors, steam drives a turbine directly for propulsion.)

Iwould say the answer would be b